A structural appraisal is undertaken to check the adequacy of an existing structure with respect to a current and future use. To carry out a structural appraisal of an existing building our qualified engineers will look at the structural safety, strength and stability of the building under normal loads and actions. We will also appraise it from the perspective of reducing its sensitivity to disproportionate collapse under accidental loads and actions. Basically we will gather information about the form and current condition of the structure and its components, its service environment and other circumstances to establish an accurate prognosis for its future use and safety.
Although several aspects of the building can be assessed based on definable qualities, suitability of the future use is largely based on details which can be established from a site inspection. In some instances, a lot less is known about the structure compared to designing a new building. There are several factors that can influence the structural behaviour and performance of buildings, such as through-life perspectives; cultural heritage issues; sources of hazard and risk; accidental loadings and actions; structural systems and materials; stability and resilience of buildings; loads and actions; verification criteria; safety considerations; material influences; defects; deterioration and damage mechanisms and sustainability issues.
Usually we will start with the review of the existing structural drawings and other relevant documents to get a full picture of the original structure as built. We will also look at any alteration or repair work undertaken and health and safety files, or any reports on previous testing done, if those are available. However, the engineers will also normally conduct an actual inspection, which might include opening- up or testing certain parts of the structure.
Once we’ve completed the review and run trough some future modelling scenarios, we will come up with the full report of the proposed changes. The report normally includes a residual service life estimation, target reliability values etc.
We use Robot for finite element and structural analysis, which if needed can be linked to BIM.